There are great opportunities to go hiking or mountain biking around the lake, or on the lake itself you can for example, hire a boat, go water skiing or wakeboarding.
The nearest town in the area is Viverone, which has given its name to the lake. In the small town centre is the old castle Il Castello di Roppolo, which dates back to 900 AD. The town is a bit back from the lake in green surroundings, characterized by the magnificent profile of the Alps in the background. If you want more culture and history, then head to Biella which is approx. 20 kilometres away, or Ivrea only 15 km away. One can easily get to Turin from here by parking in Santhià (about 10 km) and taking advantage of the free parking and trains to Turin (approx. 45 min).
There are several wineries around the lake that produce delicious wines such as Rosso di Viverone (red wine) and Erbaluce di Caluso (white wine). Viverone is not a place where you would spend several weeks as such, but the lake is a good place to take a pit stop for a few days as part of a tour or upon arrival from or before departure to one of Milan's airports.